Heater fan and temperature control settings not working

aren't there doors inside the duct that open and close as you move the controls from foot to face to defrost? could those be messed up or would that have more to do with the vacuum lines?

Yes, those doors could be stuck. It's more likely a vacuum line issue, but I've seen it where the doors were stuck as well. One of those is the most likely problem.
 
Yep check the vac lines. For some reason Jeep went with plastic tubing instead of a hose. While I did not read your original post close enough the symptoms you are having now are very simular to my experience when I got my LJ home from the PO. In that case the selection control was gone. It would blow cold or hot just not move from defrost, vent, or floor.
 
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Hate to say this, mine worked on all positions when I replaced it. Did your old one look OK? Mine was bubbled in a couple of places. Might have to open up your HVAC control centre and jumper the plug in connector for the fan switch. Just a thought
Also just remembered to get my fan to work I had to turn the actual heater control switch to any position but all the way to the left.
Hope this helps

Sorry for the delay. I posted pix of the part I pulled out. There is some bubbling on the part. The heat I’m getting from setting 1 is getting me by for now, but I’ll definitely need to get this fixed.
 
Rush,
FWIW, If the fan only blows on high, and not on 1,2 or 3, the resistor is the issue most every time. I know that was not your issue, but stay with me now. If the fan does not blow at all, the fan motor itself is toast, the resistor is also toast, a fuse blew or a wire disconnected somewhere. If you disconnect the fan motor from the electrical connector, and you add power and ground to the two connectors with jumper wires, does the fan motor spin like crazy? If not, the motor is most likely toast. It might only work enough to spin on low. If it spins super fast,that means it works. Is it POSSIBLE then, that the new resistor is not working properly? Perhaps the speed switch is the culprit instead. Make sure the blower motor works when directly wired first tho, otherwise you can chase your tail for a long time.

Thanks for the post. Remember this is a step by step and I’m a newbie. First, where is the blower motor? I assume it’s on the passenger side, sort of right on the side wall.

Even if I find it, how do I get power to it so I can test it?
 
I would go at it one issue at a time. Get the blower working on all speeds, then tackle the vent issue.

The blower should work on high even with a bad resistor. Jumper or check power and ground to motor to make sure it's good.

If you now have low speed as said with the new resistor you either installed a bad resistor (very possible, especially from Oriellys or AutoZone etc) or the switch is bad.

You can check the switch and resistor with a simple test light and the FSM, @Chris can link you to.
 
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Also, when looking under the dash, I saw this plug disconnected. I can’t seem to find the other side. Any ideas on what it is and/or where it goes?

These photos are taken from the drivers side, looking behind the gear shift. You may have to zoom to see it. I have yellow arrows pointing to the connector.
 
I'm not entirely certain, but that connector may go to a footwell light or a door chime? I'm not in front of my TJ otherwise I would look.
 
Rush, This vid should help. Jumper wires are wires you hook up to 12volts on one end and attach the other ends to the motor in question. I assume your 2003 is the same. Where he disconnects the wire bundle from the fan is where you would plug in your jumper wires. Hold the fan tightly, when you attach the second wire, if the fan motor is good, that sucker will twist out of your hand. The blower motor in my Dodge had the "I won't run unless I feel like it" syndrome, I replaced it with a new one made by the company 4-Seasons, and it fixed the issue.
 
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